The giant aggressive chondroma: A rare entity, a difficult approach.

Area of Science:

• Orthopedic Oncology
• Bone Tumors
• Skeletal Radiology

Background:

• Enchondromas are benign bone tumors typically measuring 3-6 cm in long bones.
• The risk of secondary chondrosarcoma in solitary enchondromas is up to 4%.
• The role of enchondroma size as a risk factor for malignant transformation is not well-established.

Purpose of the Study:

• To report three rare cases of enchondromas affecting the entire femur.
• To investigate the potential link between enchondroma size and malignant transformation, specifically dedifferentiation into chondrosarcoma.

Main Methods:

• Case series methodology.
• Clinical and radiological follow-up of patients with large femoral enchondromas.
• Histopathological analysis for cases with suspected malignant change.

Main Results:

• Two patients with large enchondromas demonstrated stable disease over 5 and 6 years.
• One patient, initially presenting with a large enchondroma, developed dedifferentiated chondrosarcoma.
• The patient with dedifferentiated chondrosarcoma experienced disease progression and mortality within 14 months post-surgery.

Conclusions:

• Large enchondromas, particularly those involving the entire femur, may represent a significant risk factor for malignant transformation.
• Lesion size should be considered a critical factor in assessing the risk of enchondroma dedifferentiation into chondrosarcoma.
• Further research is warranted to confirm the association between enchondroma size and malignant potential.